Problems that should be paid attention to with sewage source heat pump system

The sewage source heat pump mainly uses urban sewage as a source of cold and heat for extracting and storing energy, and uses the internal circulation of the refrigerant in the heat pump system to change the state of the refrigerant and consumes a small amount of electric energy, thereby achieving an innovative cooling and heating effect. Compared with other heat sources, the key technology and difficulty of the sewage source heat pump are anti-clogging, anti-pollution and anti-corrosion.

Wastewater source heat pump system application should pay attention to the problem:

1. Sewage water quality problems. Urban sewage includes industrial wastewater, industrial cooling water, and domestic sewage. The secondary sewage of the city is mainly through the first-level physical treatment and secondary biological treatment, which removes a large amount of impurities in the sewage, reduces the corrosiveness of the sewage, and is more conducive to the extraction of thermal energy in the sewage.

2, sewage water temperature protection issues, urban sewage cool in winter and cool in summer, year-round temperature stability, sewage water temperature in the winter than the ambient temperature 15 to 20 degrees higher, the summer temperature lower than the ambient temperature 10-15 degrees. Therefore, the heat pump has a good heat source, and the sewage source heat pump generally uses a temperature difference of 5 degrees. Therefore, the sewage source heat pump can completely operate with high efficiency.

3. The problem of ensuring the quantity of sewage: The change in the amount of urban sewage water is mainly the change of domestic sewage, and the amount of sewage discharged from domestic sewage remains basically unchanged.

4, sewage heat transfer problems, sewage contains a lot of oily dirt, flowing through the heat exchanger will have a phenomenon of hanging film, close the sticky mud, thereby increasing the thermal resistance of heat transfer, affecting the heat transfer efficiency, so design wastewater exchange When the hot water is taken away, the pipeline is taken and an automatic anti-cleaning device is set. During the operation of the heat exchanger, backwashing is performed at regular intervals to ensure the heat transfer efficiency and improve the utilization of thermal energy.